Times have changed. Russia, China’s exclusive arms supplier for more than twenty years, is now rumored to be interested in Chinese arms. The visitation of a Chinese naval task force to the Black Sea, including a modern Type 054A frigate, has sparked rumors Russia may buy a batch of the frigates to stave off a ship shortfall.

Such a sale, even if it does come off, may turn out to be a fluke of history. For all of China’s extensive efforts to build an all-encompassing domestic arms industry, there are still blind spots in her weapons production capabilities.

Mother Russia’s industry and design bureaus still crank out plenty of weapons China desires. From tanks to submarines, Russia is still a leader in weapons technology… and still the only one that will sell to China.

The sale of Russian weapons to China has always been a win-win for the two countries. China receives some of the newest and most advanced weapons systems in the world, without the cost and hassle of research and development. Russia in turn gets much-needed hard currency. As long as Russia has something to sell, this relationship won’t change any time soon.

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Here’s three weapons China should purchase from Russia.

Armata class of heavy combat vehicles

For perhaps the first time in history, China has secure land borders. Large ground forces, backed up by air and naval forces, effectively deter virtually every other state in the world from picking a fight with the People’s Liberation Army.

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Ironically, this has meant the PLA — compared to the other armed services — has benefitted the least from Chinese research and development. China’s main battle tank, the Type 99, is still a derivative of the old Soviet T-72 main battle tank, with a design that stretches back to the mid-1980s.

The adoption of the Armata family of heavy combat vehicles would transform the PLA. The T-14 Armata main battle tank is a clean break from the T-72/80/90 series of main battle tanks, using a new, longer hull. Incorporating a 125-millimeter main gun and remotely operated 7.62-millimeter machine gun, the unmanned turret is controlled by a three man crew. Active and passive protection systems, as well as a new modular armor system, incorporates the latest Russian technology.

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The T-14 Armata hull is expected to serve as a platform for a family of combat vehicles. The T-15 heavy infantry fighting vehicle would allow the PLA to transport infantry in high threat environments against the latest anti-armor weapons. Recovery vehicle and bridge layer versions are likely also in the works.

It’s important for China to have the latest tanks and armored fighting vehicles, but in the grand scheme of things they may not be important enough for China to develop them all on their own. Importing a new Russian design would allow Chinese research institutes and industry to focus on other, more important work.

S-400 “Triumf” Surface to Air Missile System

The S-400 “Triumf” surface to air missile system is one of the most advanced and capable SAMs in the world. An upgrade of the older S-300 SAM, the S-400 has quickly gained a reputation of being a one-system solution for rapid destruction of virtually any flying threat, from low-flying cruise missiles to tactical ballistic missiles.

The S-400 uses different variants of the same missile to engage different targets. The 40N6 missile provides the system’s namesake, capable of reaching out and destroying aircraft at ranges of up to 400 kilometers. The 9M96E2 missile is capable of engaging targets flying at altitudes from 5 meters to 30 kilometers at ranges of 120 kilometers, making it ideal for engaging cruise missiles. The 77N6N1 missile is capable of engaging ballistic missiles.

In April, China negotiated a deal for a regiment of S-400s for $3 billion. Each regiment consists of 36 transporter-erector-launcher vehicles, divided into six battalions.

The most likely deployment for PLA S-400s is against Taiwan, where the system will be able to detect and engage high altitude targets above the island nation. Other possibilities for deployment include Zhejiang, opposite Japan and the Senkaku Islands, Tibet and Xinjiang opposite India, Guangxi opposite Vietnam, and Yunnan opposite Burma.

In each case, the long range of the S-400 means the system could threaten adversaries over their own airspace — indeed, the S-400 could reach out and engage targets over New Delhi, Calcutta, Hanoi and Seoul.

Obviously, a single regiment will be unable to fulfill all of China’s needs. The addition of several more regiments, perhaps built under license in China, would go a long way toward improving China’s air defenses.

Yasen-class nuclear attack submarine

China’s nuclear attack submarine program has not gone off so well.

The first generation Han class nuclear attack submarines began construction in the mid-1970s. The class suffered from a number of unfortunate problems including noise and an unsafe nuclear propulsion system.

The second generation, the Shang class, had an extended development period but still failed to generate a submarine China is willing to produce in large numbers. A third generation, the Type 095 class, is currently under development.

An alternative to building the third generation would be to simply buy and license Russia’s new Yasen nuclear attack submarines. The Yasen class has a submerged displacement of 13,500 tons, length of 119 meters, speed of 31 knots, and can dive to 600 meters. Its 533 mm torpedo tubes can fire standard homing torpedoes and the P-800 Oniks and Klub missiles. It is the first Russian submarine to feature a spherical bow sonar array.

New strategic concerns would drive the sale. The introduction of new combat systems in the United States will increase China’s desire to fortify the Second Island Chain—stretching from the Japanese Island of Honshu to the Mariana Islands and Palau. India’s development of a sea-based nuclear deterrent, centered around the Arihant-class ballistic missile submarines, will necessitate an ability on China’s part to put those submarines at risk.

Kyle Mizokami is a writer based in San Francisco who has appeared in The Diplomat, Foreign Policy, War is Boring and The Daily Beast. In 2009 he cofounded the defense and security blog Japan Security Watch.

Image: Admiralty Shipyards​